I took the battery out and am not using the metronome function, but did try it out first just to see what it was like.
It's not a bad little unit, plus you are getting a nice set of isolation headphones in the deal.
Not the most versatile metronome out there, but a pretty cool combo of studio quality isolation headphones with separate metronome function.
I mean, you're pretty much going to need headphones to use a 'nome anyway, yah? This actually makes the setup a lot easier.